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ISO7810: ISO 7810/ISO 7842 Isolation Barrier Lifetime for 40 kHz

Part Number: ISO7810

When I want to build a IGBT-Driver like "Flexible High Current Gate Drive With Reinforced Digital Isolator" with an ISO 7810 or ISO 7842 there are some questions. The DC-Voltage is perhaps 750V and I switch the IGBT with 40 kHz then I have a square wave output voltage at the transformer when I want to build a DC/DC converter.

I think I stress the Isolation barrier of the ISO 7810 / 7842 with 40 kHz. The Maximum isolation working voltage refer to Figure 1 and Figure 2 in the Data Sheet of the ISO7810.

Figure 1 and Figure 2 refer only to 60 Hz.

1. How is the  Reinforced Isolation Capacitor Lifetime Projection for Devices in DWW Package when I switch with 40 kHz at a DC-Bus with 750 V ?

2. When the IOS7810/7842 isolation barrier fail - can it fail close (the isolation barrier) ?



  • Hi Frank,

    We have tested ISO78xx / ISO77xx family of devices for frequencies upto 10kHz and we do not see any degradation in any of the isolation specs. Though we do not have data for 40kHz, we expect it to support 750V working voltage. We have many customers using ISO78xx / ISO77xx at various frequencies higher than 40kHz.

    Regarding isolation barrier fail modes, please refer to the below white paper. It describes various failure modes of ISO78xx / ISO77xx in detail. Thanks.


    Koteshwar Rao